TAMKO Building Products LLC offers the
newly-upgraded TW-105 Flashing Membrane, which features white polymer surface
film technology that gives the product increased UV resistance. According to
the manufacturer, this new generation of TW-105 increases the UV resistance
from the original 60 days to an extended length of 180 days.

“We’re always looking for ways to
provide contractors with the products they need and these improvements offer
TAMKO contractors more flexibility in their project timelines,” said Stephen
McNally, TAMKO’s Vice President of Sales and Marketing.

TW-105 Flashing is a self-adhering
SBS-modified bitumen membrane used for balcony and breezeway details in
conjunction with TAMKO’s TW-60 Self-Adhering Waterproofing Membrane, TWM-1
Mastic, and either TWP-1 Adhesive Primer, TWP-2 Water-Based Adhesive Primer or
TWP-LV1 Low VOC Adhesive Primer – all part of TAMKO’s waterproofing product
line. Additionally, TW-105 Flashing may be installed at wall/floor
intersections and other transition locations.

TW-105 Flashing is available in
12-inch by 40-foot rolls and each carton contains two 40-foot rolls for a total
of 80 feet of length per carton. The product comes with a 5-year Limited
Warranty and Arbitration Agreement. It is manufactured in Columbus, Kansas, and
is available for shipping across the United States.

MFM Building
Products, a manufacturer of a full envelope of waterproofing and weather
barrier products for the building industry, offers a new innovative roof
flashing membrane – GreenWeld PVB. GreenWeld PVB armored flashing system is a
high-performance PolyVinyl Butyral (PVB) membrane enhanced with an aluminum
scrim for superior flexibility, strength and weathering. The membrane is
comprised of recycled PVB and can be used in residential and commercial roofing
applications. Typical applications include flashing for pipe penetrations and
support beams, water barrier for cavity walls, liner for valleys of shingle,
tile and aluminum metal roofs, and through-wall flashings.

GreenWeld
PVB is designed as a replacement for lead, sealant pockets or liquid flashing
systems. The membrane offers the roofing contractor significant advantages.
According to the manufacturer, it is easy to cut and use, heat-weldable,
non-toxic, sustainable, flexible and lightweight, and comes with a 20-year
warranty. Independent, third-party testing shows that GreenWeld has the same
waterproofing properties of traditional lead used to seal roof penetrations.

GreenWeld
PVB is available in roll widths of 10 inches, 20 inches and 39 inches by 19.5-foot-length
rolls. Each roll is pre-packaged in a shrink sleeve for protection until use.
Some applications require GreenWeld Adhesive/Sealant, which is also available
from the company.

For more information including technical data, installation instructions or to request a free product sample, visit www.mfmbp.com.

Cold-process fluid-applied systems combine the elastic properties of rubber polymers with the waterproofing characteristics of a highly refined emulsified asphalt. The result is a monolithic, seamless rubber membrane. Photos: Paragon Roofing Technology

Fluid-applied membrane systems have been available on the
U.S. commercial waterproofing market for many years. Originally, the systems
most frequently applied were hot-applied emulsions with or without
reinforcements. In the early 2000s, a liquid rubber membrane system was
developed that could be applied in cold-process fluid-applied applications. The
liquid rubber material combines the elastic properties of rubber polymers with
the weatherproof/waterproof characteristics of a highly refined emulsified
asphalt. The resulting formulations are proprietary materials that, when properly
applied, adhere to form a monolithic rubber membrane. The resulting membrane
can be applied to range from 20 mils to 200 mils dry.

Unlike coatings that only provide a film surface or
adhesives that require reinforcements for waterproofing capacity, the liquid
rubber forms a seamless membrane that provides instant waterproofing/weatherproofing capabilities. The material
cures within seconds to 80 percent of its full strength with full cure within
12 hours of application. The liquid rubber membrane is manufactured at the
point of application through its dual component formulation; the system
consists of a spray grade and a catalyst that are mixed together at the moment
of application through specially designed spray rig equipment. The chemical
reaction between the spray grade and the catalyst results in an instant,
seamless rubber membrane. The instant set allows the seamless membrane to be in
direct contact with water immediately. This feature also allows for the
material to be applied either horizontally or vertically up to 200 mils thick
in one application. Although the membrane still requires time to fully cure, it
is approximately 80 percent cured when the two materials come into contact.
This is a unique feature of the material, and it requires specialized equipment
and training to be applied correctly.

Advantages of Liquid
Rubber Membranes

The dual component formulation consists of a spray grade and a catalyst that are mixed together at the moment of application using specially designed spray equipment. Products are also available in one-part emulsions for application with brushes and rollers.

Liquid rubber membranes combine the properties of adhesives
and coatings while adding significant technological advancements that create an
instant-setting waterproofing/weatherproofing membrane. It is the 21st
century version of a built-up roof (BUR) system that has the performance
characteristics of modified bitumen and—because it is a monolithic, seamless
membrane—it provides a longer service life with less maintenance than other
options. Liquid rubber membranes provide economical solutions to almost all
roofing and waterproofing/weatherproofing applications and offer excellent performance
characteristics.

The primary advantages of the material are as follows:

· Superior elongation and
recovery. Structures move. Surfaces expand. Seasonal temperature changes
alter the size and shape of every object. Liquid rubber membranes have the
capacity to stretch and recover, which allows for movement of the underlying
surface. The average elongation is over 1,000 percent, and the material recovers
to 90 percent of its original state after elongation.

· Excellent adhesion. Liquid
rubber bonds to most substrates and forms a permanent bond with itself,
resulting in self-healing and self-sealing properties. The liquid rubber
membrane provides excellent adhesion to metal, wood, plastic, and concrete — even
green concrete. It also provides strong adhesion to existing construction
materials like BUR, modified bitumen, thermosets and thermoplastic membranes,
and all waterproofing materials. In most cases, no primer or tack coat is
required.

· Sustainable and environmentally
responsible. The materials contain no VOCs and satisfy EPA regulations and
environmental concerns. No special ventilation is required, as the material is
non-toxic, odorless, and non-flammable.

· Safe applications. Products
are available that can be applied with trowels or squeegees as well as a
specially designed dual-component spray rig. No heat, kettles, torches or open
flames are required in the application process. The material is safe to apply
and poses no health risks to the applicators.

Another advantage of the liquid-applied system is that the material is self-leveling. This allows the membrane to conform to substrate irregularities and provide a continuous seal at penetrations, which are typically the most difficult details in roofing applications.

Another primary advantage of the liquid rubber membrane
system is that the material is self-leveling. This allows the membrane to
conform to substrate irregularities and provide a continuous seal at
penetrations, which are typically the most difficult details in roofing
applications. The instant, full adhesion of the membrane allows for continuous
system application without additional components that would be required with
other membrane applications. This eliminates the chances of deformation from the
breakdown of different material system components. It also eliminates some of
the application errors associated with multi-component systems.

Deformations of one of the materials in the multi-component
system can lead to failure of the total system. Examples of typical defects in
roofing systems include loss of attachment from improper adhesive application
at substrate, insulation or membrane; improperly aligned insulation; loss of
attachment of insulation due to substrate irregularities; voids in membrane attachment
that lead to blisters and/or ridges; and slumping or buckling flashing due to
improper attachment. The improper attachment of one component leads to
differential movement in the system.

Liquid-applied systems form a monolithic membrane, eliminating
the most vulnerable point of rolled membranes for moisture infiltration: the
seams. The superior adhesion characteristics to all types of substrates and
materials also eliminates the chances of moisture infiltration under the
membrane.

While overspray is minimized in liquid rubber membrane applications, precautions should still be set at perimeter building locations and application should not be attempted in high winds.

The elongation and flexibility of liquid rubber membrane
exceeds industry standards. This allows it to withstand typical thermal cycling
and perform well in extreme heat and cold. Application temperatures are wider
than most other adhesives and coatings, and range from ambient outside
temperatures of 20 degrees Fahrenheit to over 100 degrees. The membrane is
naturally UV resistant and can be exposed throughout the lifetime of the
membrane. The membrane is compatible with all types of reflective coatings if
application is required. Granule surfacing can also be applied.

The membrane is also very durable. Depending on applied dry
mil thickness, the membrane can withstand heavy force and is puncture resistant
with self-healing and self-sealing properties.

The membrane can be applied over damp surfaces and it can be
exposed to ponded water in unlimited duration. The material has been used as
pond liners and in containment tanks since its introduction to the market. The
water absorption rate is less than 1 percent—well below ASTM’s minimum water
absorption rate of waterproofing materials, which is 5 percent.

Benefits for
Applicators

There are significant benefits to applicators of liquid
rubber membranes. The foremost benefit is the reduced crew size required for
application. This is an important consideration due to the severe labor
shortages affecting the construction industry.

In most cases, a crew of three properly trained and
experienced applicators using one spray rig can complete up to 10,000 square feet
in one day. Additional hoses and/or spray rigs can double or triple those
production rates.

In addition to the advancements in material technology,
there are vast improvements to the specialized equipment used in the
application process. The spray equipment is now portable and can be transported
to construction sites without heavy trucks and covered trailers. The spray
equipment is also lightweight and can be easily positioned on roof areas or
waterproofing trenches. This equipment is housed on four-wheel carts for easy
transport throughout the construction site.

The spray equipment consists of a high-volume, low-pressure
system. The dual component equipment mixes the two components outside the gun to
form a monolithic membrane upon impact with the substrate.

The equipment has a direct drive system to eliminate downtime
associated with traditional belt drive systems. The application rate averages
up to 1,000 square feet an hour for one gun. The equipment can run two guns at
the same time, which increases production to 2,000 square-feet per hour. It can
run up to 600 feet of hose and the material can be contained in everything from
a 5-gallon pail to a 275-gallon tote. The most common container is a 55-gallon
drum.

The spray guns have also improved. Advancements in manufacturing have eliminated most of the clogging issues
that plagued spray guns in the past. The spray guns are lightweight and can be
disassembled rapidly if material clogs occur. The older spray guns took up to
an hour to take apart in the event of material clogs.

Overspray—a common problem with most spray applications—is
minimized in liquid rubber membrane applications because it is a low-pressure
application and the material cures instantly after release from the spray gun.
Precautions, such as coverboards, should still be set at perimeter building locations
and application should not be attempted in accelerated wind conditions, but the
chances of excessive overspray are minimal.

Liquid Membranes and
Roof Restoration

Because of their waterproofing/weatherproofing capacity,
instant cure set, adhesion success with most substrates and materials, wide range
of application temperatures and membrane mil thickness that can range from 20
mils to 200 mils dry, liquid rubber membranes can perform in most building
exterior applications, including new and remedial roofing applications. At this
time, the systems are being used primarily as roof restoration and repair
products.

Typical roof restoration projects include applications over
built-up roof systems (asphalt and coal-tar), thermoplastics, EPDM, sprayed polyurethane
foam, metal and tile. The liquid rubber membrane systems were designed to
significantly extend the service life of the existing roof system. They are also
excellent for repairing flashings and penetrations. The spray equipment is
small and mobile and most repairs can be completed with minimal manpower.

When it is applied by knowledgeable installers, the system
is an excellent economical choice for building owners. The initial step in the
restoration process is the proper repair of the existing roof system and
preparation of the surfaces. All surfaces should be free from any loose dust,
debris, oil, grease or foreign material. These items should be removed prior to
application by means recommended by the manufacturer. The liquid rubber
membrane can be applied over damp surfaces; however, extensive ponding water
should be removed prior to application.

Proper roof repairs should be completed in compliance with
roofing industry standards. The one-part emulsion can be used for repairs to
the existing membrane. Reinforcements should be added as required. All cracks,
penetrations, existing seams, corners should be addressed using polyester
fabric with roller/brush or trowel grade.

Once proper repairs and preparation are completed, the
liquid applied membrane can be applied to the existing roof surface. For most
roof membranes and substrates, a light rinse/power wash of the surface is all
that is required. A primer is required over existing EPDM membranes.

The other exception is on aggregate surfaced built-up roof
systems, which require additional preparation. Removal of all loose aggregate
is required. On asphalt-based BUR, the liquid applied membrane can be applied
directly over the prepared surface. For coal-tar based BUR, a
manufacturer-approved fabric is required due to the gassing of the coal tar. The
reinforcement should be set in a 20-mil wet profile of one-part liquid rubber.
The reinforcement shall be set in a full and even application so that it is
fully adhered with no wrinkles, buckles or blisters. The liquid rubber membrane
is then set over the reinforcement. For best application practices, the
reinforcement should be set in place with a soft-bristle broom.

The application of moisture relief vents is also required on
BUR systems to prevent gassing of bitumen, which could contribute to blisters.
Typical applications require one vent for every 1,000 square feet. Additional
vents may be used in areas with existing moisture in the system.

Once the preparation and proper repairs have been completed,
the liquid rubber membrane can be applied. Application can be completed with
brush, roller or trowel in smaller application areas. Spray grade material
shall be applied using specialized equipment. Apply material in a full and even
application. Always apply it in strict accordance with manufacturer’s
recommendations and approved submittals.

Stir materials during application in accordance with
manufacturer’s instructions to avoid product separation. Applicators should spray
the fluid component as a continuous, monolithic and seamless membrane of
uniform thickness, beginning at the lowest point and terminating at the highest
point. In the event the membrane is applied too thin, contact the manufacturer
for recoating guidelines. Prior to application, create a grid across the roof
with spray paint, allocating one drum of material per section of the grid.
Perform cut-outs to check mil thickness and retain samples. Typically, three
test cuts are to be taken per 1,000 square feet. In addition, continuously
check wet millage by using the “T” post on a caliper mil gauge. After the
liquid rubber membrane has cured, apply trowel adhesive to any visible voids.
Comply with the manufacturer’s recommendations for proper membrane
terminations.

Ultraviolet stabilizers are added into the material
formulation so the completed liquid applied membrane does not require
additional surfacing for UV protection for short term (less than ten years)
exposure. Long-term exposure (and warranties) require that some sort of surfacing
is applied for additional reflectivity or protection. A variety of surfacing
materials, including coatings, granules, pavers and living roof applications
can be applied.

Liquid-applied membranes are typically eligible for
warranties from 10 to 25 years. Contact the manufacturer for warranty
requirements.

About the author: John A. D’Annunzio is the owner of Paragon Roofing Technology, headquartered in Troy, Michigan. He has been involved in testing, evaluating, and designing roofing and waterproofing materials and systems for more than 30 years. For more information, visit www.paragonroofingtech.com.

Detec Systems has developed the IntegriScan scanning platform. According to the company, this is the only testing method capable of Electronic Leak Detection (ELD) testing of conductive membranes including Black EPDM and semi-conductive waterproofing systems. Black EPDM contains carbon black, which produces a level of electrical conductivity that makes testing impossible using high voltage and vector mapping.

In order to enable valid ELD testing of Black EPDM, TruGround Conductive Primer must be applied directly below the membrane per ASTM D7877. TruGround can be used for quality assurance testing on newly installed, fully adhered or mechanically attached EPDM membranes. Once applied, ELD testing can be performed for the life of the roof. Future breaches or seam voids can be quickly pinpointed allowing repairs to be done immediately, preventing costly moisture damage to occur. The IntegriScan and TruGround are compatible with all membranes including EPDM, TPO, PVC, modified bitumen, and hot and cold fluid-applied waterproofing.

What is the number one goal of any building owner when it comes to the roof? They don’t want water pouring through their ceilings damaging the interior of the building. How do you keep water out of the building? By keeping the water on the exterior of the building and directing it to the roof drains or other drain locations, such as scupper or gutters. The roof drain is, on a basic level, one of the simplest details on the roof, and yet it is flashed incorrectly time and time again. This paper will walk you through the process of replacing a roof drain on a structurally sloped steel roof deck and installing the new roof system and flashing.

Photo 1. The sump pan and drain body have been installed. Photos: Hutchinson Design Group Ltd.

First off, we are going to assume that the current drainpipe is adequate to handle the existing water volume and drain its portion of the roof, and that the drain pipe is in good condition. Our new roof system will meet the current R-30 requirements for continuous insulation above the roof deck in a roof near Chicago. So, our roof system will be composed of a mechanically fastened substrate board on the steel roof deck, a self-adhering vapor retarder, two layers of 2.6-inch insulation mechanically fastened, a 1/2-inch modified gypsum cover board set in bead foam adhesive, and fully adhered EPDM membrane. (See Figure 1.) We will also assume that the roofing contractor is acting as the general contractor for our scenario.

Now that we have our parameters out of the way, what’s first? I have never met a building owner that likes construction debris inside of their conference room or classroom, so the interior needs to be protected prior to the removal of the existing roof drain. This can be as simple as some Visqueen, but the interior protection needs to be installed prior to the removal of the existing roof drain. The one question that seems to come up is, who is installing this protection? The owner? The plumber? The roofing contractor? I like to put this on the plumber. He knows when he is removing the drain and installing the new one.

Once the interior protection is installed, we need to coordinate the removal of the existing roof system and installation of the vapor retarder with the removal of the existing roof drain, as well as the installation of the new metal sump pan, drain body and lead and oakum joint to the existing drain pipe. (See Photo 1.) This all needs to be done on the same day so that the roof can drain properly and that the vapor retarder can be terminated onto the roof drain flange. This part is critical, as with experience this designer has learned that the vapor retarder can be used as the seal between the extension ring and the roof drain flange and that the O-ring can be eliminated. The sump needs to be fastened to the roof deck around the perimeter at 8 inches on center and be centered on the drainpipe. The drain body then needs to be set over the drainpipe and lead and oakum installed between the drain body and drain pipe.

Installing the New Roof

So, now we have the roof drain body and the vapor retarder installed. Now comes the new roof system. To meet our R-30 requirements, we are going to need a base layer of 2.6-inch polyisocyanurate insulation and 4-foot-wide, 1/2-inch-per-foot tapered insulation sump around the roof drain. This sump will get us to the R-30 requirements of 4 feet from the roof drain as required by the current codes. If my math is correct, that will leave 3.1 inches of insulation at the roof drain. We will need a reversible collar and threaded extension ring to accommodate this height. When setting the reversible collar onto the drain bowl, set it in water cut-off mastic. If the drain ever becomes clogged, this will help to keep water from seeping under the reversible collar and into the roof system. Next the threaded extension ring is installed. First, install some water cut-off mastic onto the treads prior to engagement with the reversible collar. Once again, this will help to prevent water from entering the roof system if the drain becomes clogged and backs up.

Photo 2. The extension ring has been set lower than the cover board (yellow) and water cut off mastic has been installed on the extension ring flange. Photos: Hutchinson Design Group Ltd.

One of the main questions that I receive from the roofing and plumbing contractors is, “How high should I set the extension ring?” Well, it varies per roof system, but for our scenario it needs to be set flush with the top of the tapered insulation. We set it here because we have our cover board that has yet to be installed, and when the clamping ring is installed it will be lower than the cover board. Now back to the insulation; the 2.6-inch insulation should be installed as close to the extension ring as possible, chamfered as required to fit under the flange. Next the tapered insulation sump is installed. This should be installed as close as possible to the extension ring flange and chamfered as required to fit beneath the flange. All voids between the extension ring and the insulation should be filled with spray polyurethane foam insulation.

Once we have our insulation installed, next comes the cover board. The number one thing with the cover board and roof drain is having the cover board cut perpendicularly to the roof drain flange. (See Photo 2.) Do notchamfer the cover board. Chamfering the cover board may ease the transition of the membrane onto the extension ring flange, but it creates an unsuitable substrate surface for the bonding adhesive. And in my experience, water seems to end up ponding around the roof drain and not dropping into the roof drain. This will also allow the roof’s drain clamping ring to sit flat and below the roof surface of the roof.

Photo 3. The membrane has been correctly cut in a cloverleaf pattern. Photos: Hutchinson Design Group Ltd.

Now that our cover board is installed, we have the membrane and its transition into the roof drain. Water cut-off mastic is to be installed on the extension ring flange. How much you ask? One tube. Load that flange up. Make two thick beads with it. I have never heard a contractor say, “Man, using all of that water cut-off mastic on the job really set me back.” It’s a small item, but it is worth it.

After the membrane has been installed and the clamping ring is set, it’s time to cut a hole in the membrane to allow the water to get to the drain and off the roof. How big should the hole be? As small as possible is what some contractors might say. I ask a question to you now: what is the goal of the roof drain? If you answered to get the water off the roof as quickly as possible, you would be correct. Then why would the contractor want to cut a small hole in the roof membrane that would restrict the flow of water into the roof drain piping and off of the roof? I am dumbfounded as well. When we detail the roof drain, we call for the membrane to be cut back to within a 1/2 inch of the extension ring in a cloverleaf pattern around the clamping ring bolts. (See Photo 3.) This way there is no confusion on how far back the membrane is to be cut. Set the drain dome and the roof drain detail is complete.

So, there you have it. Now the roof can drain properly with a brand-new roof drain with no problem (fingers crossed).

Regular roof inspections give consultants and contractors a chance to maintain relationships with building owners and managers and create value beyond any immediate repairs.

Commercial roofs should be inspected at least twice a year, typically in the spring and fall. Roof inspections are also advised after major weather events, though contractors may already be deluged with repair requests. Of course, building managers will be more receptive to discussing regular inspections during such times, even though time is short. A service flyer and readily available letter-of-agreement can help quickly close the deal, and be used after any major job throughout the year to create recurring business. Customers should clearly understand the service offer and any special provisions for emergency repairs or exceptions such as during wider emergencies.

Common Sources of Roof Leaks

Cracks in or around flashings and penetrations

Breaks in and around gutterways and drains

Poor drainage or debris-clogged drainage systems

Storm damage, tree branches, ice dams, etc.

Incidental damage by other trades during construction or maintenance

Excessive foot traffic at rooftop access points and around HVAC units and other rooftop infrastructure

Old or deteriorating roofing materials

While roof leaks can be caused in several ways, many common sources of leaks can be prevented with liquid-applied coating and membrane systems that fully adhere to substrates and are both self-terminating and self-flashing. Membrane systems are fully reinforced and create a seamless surface. High-quality systems are designed to withstand ponding water, ice, snow, UV light, as well as most chemicals. Unreinforced roof coatings can be used for repairs or complete restoration of the roof surface.

If only a small area is damaged, a limited repair is best, and usually possible with compatible materials over an existing system in good condition.Check if a warranty is in place, and if possible contact the manufacturer before the repair. Perform any repairs within the guidelines of the warranty.

For wider areas, a roof recovery is often possible right over the existing roofing. If interior leaks from a field area are evident, core samples can verify the condition of the existing roof assembly down to the deck. Built-up roofs (BUR), in particular, are susceptible to sun and temperature cycling. Tiny spider cracks and micropores can develop in the surface, and the layers below can absorb moisture and deteriorate. Water always travels to its lowest point and, if left unchecked, will damage the underlying structure.

On low-slope roofs, areas of ponding water are a prime target for inspections. If the roof is covered by aggregate or overburden, it must be cleared from around the lowest point of any low-lying areas, and other areas of suspected damage. A visual inspection can locate the source of an active leak, but there may be more than one source or a larger issue that may not always be visible. Broader sampling is needed to evaluate the general condition of the roof and the scope of any deterioration.

Quality workmanship and materials help avoid callbacks and ensure long-term relationships. After completing any necessary repairs, a PMMA, polyurethane or elastomeric membrane or coatings system can be installed to extend the service life of an existing roof. Elastomeric-based coatings are generally the best value for straightforward repairs and can be ideal for recovering metal roofs. Roof restoration, in general, can enhance building performance with “Cool Roof” products, especially those with a high solar reflectance index (SRI).

At the end of the day, an ounce of prevention and a prompt response to issues can help building owners avoid expensive headaches. People remember expert advice and quality service, especially in times of need. They also may tell others — which is another way regular inspections can help keep the door open to recurring business.

The roof on the new Goodman Logistics Center (the building on the right) encompasses more than 1 million square feet. The roof system installation met an aggressive timeline that spanned the winter months. Photo: Goodman Carlisle LLC

Goodman, an international commercial and industrial property group, approached Donald B. Smith Inc. of DBS Roofing in November 2017 to support the roofing of the company’s new Logistics Center in central Pennsylvania.

Founded in 1948, DBS Roofing is a second-generation, privately held company whose principles of quality and workmanship have earned the team countless awards. Among those honors include the Firestone Master Contractor recognition, the Baltimore Builder’s Exchange “Craftsman of the Year Award” and numerous industry publication recognitions for notable projects.

The Logistics Center roof was 1,010,000 square feet and was established on a very aggressive timeline that spanned through the tough Northeast winter months. The initial specifications of the job called for a mechanically fastened TPO roof system, which was going to be challenging with the size and timeline of the project. Additionally, the condensation levels in central Pennsylvania are not ideal for mechanically fastened solutions, as it would require applying a vapor barrier and foam around all perimeters, exceeding the original budget and schedule.

To save time and keep the project moving forward during the unfavorable winter conditions, DBS Roofing elected to use one of the company’s favorite “box world” solutions — Firestone Building Products (FSBP) UltraPly TPO SA with Secure Bond Technology.

Photo: Goodman Carlisle LLC

The TPO roofing system is comprised of a self-adhering membrane with factory applied, pressure sensitive adhesive and technology designed to ensure uniform adhesion coverage across the entire membrane. According to the manufacturer, the system can be installed in weather as cold as 20 degrees Fahrenheit.

“Commercial roofing in central Pennsylvania can be very challenging during the winter season, but Firestone UltraPly TPO SA allows our business to continue working through those conditions and prosper,” says Donnie Sanders, president of construction, DBS Roofing. “Being able to apply the Firestone TPO SA at 20 degrees resulted in a successful year for us.”

The Goodman Logistics Center roofing project began on November 1, 2017 and was completed on time March 1, 2018.

The new Under Armour distribution warehouse roof encompasses 1,286,000 square feet. It was topped with a TPO roof system manufactured by Johns Manville. Photo: Orndorff & Spaid Roofing Inc.

Industrial projects exceeding one million square feet of roofing might give some contractors pause, but at Orndorff & Spaid Roofing Inc., it’s just another day at the office.

The third-generation family run roofing contractor has been in business since 1953. Orndorff & Spaid services the Baltimore-Washington metro area, as well as parts of Virginia, Pennsylvania, and Delaware. It focuses primarily on large-scale commercial projects, including warehouses, distribution centers, retail businesses, schools and data centers.

Orndorff & Spaid routinely tackles roofing projects up to 1.5 million square feet. The company strives to keep as much work as possible under its own control, and the necessary supplies and equipment are always on hand at its 13-acre headquarters in Beltsville, Maryland.

“We’re a little bit unique as a roofing company in that we self-perform almost everything,” says Richard Harville, vice president of estimating. “We have our own cranes, all our own lifts. We do our own trucking. We have an in-house mechanic’s shop that repairs all of the equipment. All fuel servicing is done from our yard here. We also warehouse a fair share of material here because the logistics of running a job.”

Photo: Johns Manville

A recent new construction project at the former location of a Bethlehem Steel factory in Tradepoint St. John’s was right up their alley. “This was a new construction project, fairly conventional in most regards except for one, and that had to do with the site,” notes Harville. “Most of the site had been infilled over the years, and there was a lot of slag and other materials on this site, so it is not bedrock, for sure.” Due to the potential for movement, seismic expansion joints were specified. The gaps in the deck were as wide as 9 inches.

The owner of the complex was kept under wraps during construction phase, but the completed Under Armour distribution warehouse is now an area landmark. The roof encompasses 1,286,000 square feet, and the project had to be completed under a very tight schedule.

The general contractor on the project, FCL, reached out to Orndorff & Spaid during the design phase, and they recommended a TPO roof system manufactured by Johns Manville.

Harville shared his insights on the project with Roofing, along with members of the project team including Dane Grudzien, estimator; Carl Spraker, project manager, single ply; and Mike McKinney, project manager, sheet metal.

The Clock Is Ticking

Work began in April 2017 with a deadline to finish by the end of July. “The schedule was what made this project difficult,” notes Harville. “They had an end user set to come in and they were in an extreme hurry to get this thing done.”

Harville and Spraker were confident the experienced team would be up to the task. “Once we got our bearings, we rock and rolled this job,” Spraker says. “We had up to 40 employees on the site and worked six days a week.”

The roof system installed over the structure’s metal deck included two layers of 2.5-inch polyiso and a 60-mil TPO membrane. “This job was mechanically attached at 6 inches on center, with perimeter and corner enhancements as required by FM,” notes Grudzien.

The roof installation began with a 10-man crew, and crews were added as the work ramped up. “We ended up with four 10-man crews, with the foreman on the first crew in charge the team,” Spraker recalls. “We just did as much as we could every day and kept track of everything. We averaged 700 squares a day. One day we did 1,000 squares.”

Crews worked on half of the building at a time, with falling back as needed to install flashings or strip in the gravel stop. “We started on one side of the building and went from end to end, following the steel contractor,” says Spraker. “When we finished one side, we came all the way back to the end where they started and followed them down the opposite side.”

The roof also incorporated 276 VELUX skylights to illuminate key areas of the facility. Logistics Lighting delivered them all in one shipment, as Orndorff & Spaid requested. The 4-foot-by-8-foot skylights were stored on site and loaded to the roof with a crane for installation after a plasma cutter was used to cut holes in the deck. Prefabricated curbs were installed and flashed. “I had a separate crew designated just to install skylights,” Spraker notes

Safety precautions included perimeter warning lines, and workers outside that area were tied off 100 percent of the time, as they were when the skylights were installed. AES Raptor TriRex Safety Carts were used as anchor points.

Safety is always crucial, notes Harville, and the company makes it a priority on every project. “Our safety parameters go above and beyond standard state or federal mandating,” he notes.

Metal Work

The scope of work included large external gutters, downspouts and edge metal. According to McKinney, the sheet metal application was pretty straightforward. “There was just a lot of it — long, straight runs down two sides,” he says. “The coping was installed on the parapets on the shorter ends.”

Gutters were installed after the roof system was in place. “The roof wasn’t 100 percent complete, but once areas of the roof were installed and the walls were painted white, we could begin to install the gutters,” says McKinney. “After work was completed on one side, crews moved to the other side.”

The large gutter featured internal and external hangers, alternating 36 inches on center. All the metal was fabricated in house, and the exterior hangers were powder coated to match the steel.

Once the external hangers were installed, the gutter sections were lowered into place and secured by crew members in a man lift. “Once you had your hangers up, you could just lower the gutter over the side and into the external hangers,” McKinney explains. “We put the internal hangers into place after that. After the drip edge is installed, the single-ply crews come back and flash the drip edge into the roof system.”

Installation of the downspouts had to wait until the walls were painted. One wrinkle was the change in color of the downspouts. About two-thirds of the way up the wall, the paint scheme went from black to white, and the building owner wanted the downspouts to change colors to match. “We reverse-engineered it,” notes McKinney. “We measured from the paint line up and put in a 30-foot section of downspouts there, because we put our bands at the joints and we didn’t want to have the bands too close together in the middle of the wall.”

Talented Team

The project was completed on budget — and a month early. FCL hosted a barbecue to celebrate. “FCL had a big cookout for the contractors with a steak dinner for everyone,” notes Harville. “They really went over and above on that.”

The Orndorff & Spaid team credits the effort of all companies involved for the success of the project. “The steel contractor was phenomenal, and FCL did an excellent job of coordinating everything,” Spraker says.

The manufacturer also did an excellent job, notes Harville, who commended the work of Melissa Duvall, the JM sales rep on the project, and Barney Conway, the field rep, who visited the site at least once a week. “JM did a good job keeping us well stocked with material and getting us deliveries when we needed them,” Harville notes.

The team members at Orndorff & Spaid believe their confidence comes from experience and knowing that most of the variables are under control. “A lot of that has to do with the equipment we can bring to bear when we need to,” Harville states. “We control the logistics all the way through. Most companies are going to rent a crane or hire trucking — we do all of that. We have our own lifts, we have our own cranes, we do all of our flatbed trucking. We bring a unique process to the table. Beyond that, and our project managers are well versed at doing this. It’s not our first rodeo.”

Roofing professionals install a new asphalt roof on the Broward County Stephen Booher Building in Coral Springs, Florida. Photo: Advanced Roofing Inc.

A low-slope asphalt roofing system is cost effective, durable and reliable. Multiple layers of weatherproof membranes protect a building, its residents and the property it houses. There are a few design elements that will help building owners get the most from their roofing system. Managing ponding water is essential to properly maintaining a roof.

Ponding water is defined as the water which remains on a roof 48 hours or longer. Water may accumulate on a low-slope roof due to rain, snow or runoff from rooftop equipment. Ponding water can have major negative consequences, regardless of the type of roofing system. Proper design, installation and maintenance of roofing structures can prevent this condition and its associated problems.

The adverse effects of ponding water on roofs can include:

Deformation of the deck structure:Ponding water can substantially increase the load on roof decks. As water accumulates, deck deflections can increase, thereby resulting in additional ponding water, which could compromise the structural integrity of the deck.

Damage to the roof surface:Ice formations develop and move constantly with changes in temperature. This movement can “scrub” the roof membrane to such an extent that considerable physical damage to the membrane can occur.

Growth of algae and vegetation:When water stands for long periods of time, algae and vegetation growth will likely occur, and may cause damage to the roof membrane. Additionally, vegetation can clog drains and cause additional ponding.

Accumulation of dirt and debris in the ponding area:Dirt, debris, and other contaminants can affect and damage the membrane surface. The can also lead to clogged drains.

Proper design and installation are crucial factors in roof system performance. This photo shows an Atactic Polypropylene (APP) modified bitumen membrane being applied by torch to a low-slope roof. Photo: ARMA

Ponding water may lead to accelerated erosion and deterioration of the membrane surface that can result in failure of the roof system. Allowing even relatively small amounts of moisture beneath the roof membrane may reduce the thermal efficiency of the insulation. More importantly, moisture intrusion can cause serious damage to the deck, insulation, and membrane as well as the building’s interior.

The Asphalt Roofing Manufacturers Association (ARMA) recommends that roof designs provide adequate slope (minimum of ¼ inch per foot) to ensure that the roof drains freely throughout the life of the building and to thereby avoid the effects of ponding water. Model building codes also require a minimum ¼ inch per foot slope for new construction projects, and require positive drainage for re-roofing projects. These requirements are intended to prevent water from ponding on roof surfaces.

Managing Ponding Water

Here are a few best practices to manage ponding water:

Adequate sloping should be taken into account during the design process. A roof’s structural frame or deck should be sloped, and drainage components like roof drains and scuppers should be included in the design.

In addition, secondary (or emergency) drains may be required by local plumbing codes to help reduce the risk of a structural failure due to clogged drainage systems. Talk to your roof membrane manufacturer and/or roof system designer to determine the proper location of these components.

If a deck does not provide the necessary slope to drain, a tapered insulation system can be used. A combination of different approaches — single slope, two-way slope, and four-way slope — is often used to achieve the necessary slope and to allow for moisture drainage.

Additionally, crickets installed upslope of rooftop equipment and saddles positioned along a low-point between drains, can help prevent localized ponding in conjunction with a tapered insulation system.

Building designers and owners should work with contractors and roof manufacturers to determine which methods are best and appropriate for a roof assembly’s long-term performance, whether it’s a new construction or re-roof project.

The NRCA Roofing Manual: Membrane Roof Systems—2015, states the following: “NRCA recommends that designers make provisions in their roof designs for positive slope.”

The manual spells out that slope generally is provided by:

Sloping the structural framing or roof deck

Designing a tapered insulation system

Proper location of roof drains, scuppers and gutters

A combination of the above

By following the proper drainage practices detailed above, building owners can positively impact their low-slope roofing system and help to ensure it will remain durable and reliable throughout its service life.

The 170,000-square-foot roof of Quicken Loans Arena was completely restored using a liquid-applied system from Tremco Roofing. Photos: Tremco Roofing and Building Maintenance

Re-roofing sports and entertainment venues presents its own set of challenges. Sports arenas usually host concerts and other events, so scheduling and logistics can be difficult. Quicken Loans Arena in Cleveland — also known as “The Q” — is home to the Cleveland Cavaliers of the NBA, and it hosts some 200 other diverse events every year, including concerts and conventions. In 2015, realizing the roof was reaching the end of its useful life, the owners looked for advice on their next move. A team of roofing professionals recommended a roof restoration system that would provide the protection and recreate the aesthetics of the original roof — and keep disruption to the facility at a minimum.

Ohio companies stepping up to help the home team included architect Osborn Engineering, headquartered in Cleveland; roof consultant Adam Bradley Enterprises of Chagrin Falls; roofing manufacturer Tremco Roofing and Building Maintenance, headquartered in Beachwood; and roofing contractor Warren Roofing & Insulating Co., located in Walton Hills. After comprehensive testing revealed that more than 90 percent of the roof could be restored, they developed a plan to clean, repair and completely restore the 170,000-square-foot main roof of Quicken Loans Arena using a liquid-applied system from Tremco Roofing.

John Vetrovsky of Warren Roofing and Joe Slattery of Tremco Roofing shared their insights on the project with Roofing magazine. Both men were brought in during the planning stages of the project and saw it through to completion. “We were helping to budget the project with Adam Bradley and Osborn Engineering,” notes Vetrovsky. “They were asking about a few different systems, and the Tremco system was the best fit for the project.”

Warren Roofing has served the greater Cleveland and Akron area since 1922, and Tremco’s roots in northeast Ohio go back to 1928. Warren Roofing served as the general contractor and roofing contractor on the project. The scope of work included updates to the lightning protection system, the safety cable system, and the heat trace system used to melt snow in the gutters.

Repairing the Existing Roof

The existing system was the structure’s original roof. It was 24 years old, and consisted of a mechanically attached hypalon membrane over two layers of polyisocyanurate insulation totaling 3 inches. The roof membrane was showing some wear, and sections had sustained damage from an interesting source: fireworks from nearby Progressive Field, home of the Cleveland Indians, launched after the Indians hit home runs. After the damage was detected, the team changed the direction the fireworks were launched, and the problem ended.

Crews from Tremco Roofing cleaned the roof using the company’s RoofTec system, which recaptures the water and returns it to a truck to be filtered. Photos: Tremco Roofing and Building Maintenance

Despite the damage, visual analysis and a nuclear roof moisture test using a Troxler meter confirmed the roof was an excellent candidate for restoration. “There was some wet insulation and warped insulation, and we marked off those areas that had to be replaced,” notes Slattery. “It was a small fraction of the total job.”

Crews from Warren Roofing removed and replaced the damaged insulation, cutting through the membrane all the way down to the existing 6-mil vapor barrier on the deck. “All of that insulation had to be stair-stepped back so we could properly lap in the new material,” Vetrovsky says. “We got rid of all of the damaged insulation, and we repaired the vapor barrier. Then we staggered the two new layers of insulation, matching the existing thickness.”

Where possible, the existing membrane was pulled back and glued into place. In sections where new membrane was needed, crews adhered pieces of EPDM.

The plan specified adding the fasteners in the existing roof and any repaired sections before the coating system was applied. Tremco Roofing conducted uplift testing through Trinity ERD to ensure the results met or exceeded the specified design. “There was a significant upgrade to the fastening,” Vetrovsky says. “Because of the shape of the building, the perimeter enhancement was probably the greatest I’ve ever seen.”

Screws and 3-inch plates were used. In the field, the minimum was 4 feet on center, 12 inches apart. In the perimeter, fasteners were installed 2 feet on center, 8 inches apart. “It worked out nicely because the fastening ended up in the middle of the sheet, and now the sheet has fasteners that are original at the seam, and a foot or two over, there is a row of new fasteners,” notes Vetrovsky.

Cleaning Up

Prior to the fasteners being installed, the membrane was cleaned by crews from Tremco Roofing using the company’s RoofTec system. “We cleaned the membrane no more than 30 days ahead of what Warren Roofing was doing,” notes Slattery. “We had to mobilize at least three times to clean the roof so the time elapsed would never be more than 30 days.”

The three-step restoration process consists of a primer, a base coat with a fiberglass mat embedded in it, and a topcoat. Here, crews embed the fiberglass mat in the base coat. Photos: Tremco Roofing and Building Maintenance

The cleaning solution is applied using a custom-designed tool that looks like a floor polisher. It has a 2-foot diameter head that spins to clean the surface and a vacuum that recaptures the water, which is returned via hoses to a truck so contaminated waste water, environmental pollutants and high-pH cleaning solvents can be filtered out. “All of that water goes back into the sanitary system after it’s filtered,” Slattery explains. “It does not go into the sewer system.”

“It’s very fast, it’s very effective, and it’s very efficient because you can easily see the areas that have been cleaned,” notes Vetrovsky. “With power washing, you don’t have any way to filter the water.”

The biggest challenge on the cleaning portion of the project was the arena’s sheer size. Approximately 500 feet of hoses were needed to supply water and return it to the truck for filtering.

Cleaning of the substrate is a crucial step, according to Vetrovsky. “The system really does a nice job cleaning the membrane, and that is the key to any restoration project,” he says. “You’re only as good as the surface you’re applying it to.”

Applying the New Roof System

After the sections were cleaned, crews installed the liquid-applied AlphaGuard MT system. The three-step process consists of a primer, a base coat with a fiberglass mat embedded in it, and a topcoat. In this case, the primer was applied with rollers. “The area that we primed each morning was the section we would apply the first coat of AlphaGuard MT with the fiberglass mat that afternoon,” Vetrovsky says. “We did not prime ahead. We didn’t want to take the chance of dust adhering to the primer.”

The top coat was applied with both rollers and spray equipment. Photos: Tremco Roofing and Building Maintenance

Care had to be taken with the schedule to complete the work efficiently. “Once the base coat is on, you have 72 hours to apply the top coat,” Vetrovsky explains. “We would install the base coat and the fiberglass mat for two to three days to get a big enough area. The topcoat would go on faster because you’re not embedding any mesh into it. You really had to always keep an eye on the future weather to make sure you could get the topcoat on within the 72 hours.”

The topcoat was applied with both rollers and spray equipment. After the topcoat was applied, crews installed a second coat with sand embedded in it as a wear surface. Because of the roof’s curved surface, walk pads were not feasible, so the sand was used to provide additional traction for any workers conducting ongoing maintenance.

The sand was broadcast by hand and back-rolled into the coating to maintain a uniform appearance. “Part of this project was to make sure the sand looks uniform when it is visible from a blimp overhead,” notes Vetrovsky. “That was a difficult task, but the guys did a great job.”

The roof features three different finish colors, which were custom designed to match the roof’s original color scheme. The main roof is light gray, with black under the large LED sign. The sections over the wings are white, as are the 2-foot-wide stripes.

“They wanted black under the new LED sign so it would really show the letters nice and clear, even during the day,” says Vetrovsky. “We also put the white stripes back to match the roof’s original appearance. That was a challenge, to keep everything straight. It’s hard to chalk lines on a curve, but it came out nice. Everything matches what the original roof looks like.”

Penetrations for the sign included round posts that held the rails about 2-1/2 feet above the roof level. The liquid-applied membrane made coping with details easy, according to Vetrovsky. “The liquid membrane makes the flashing details all one piece with the roof system,” he says. “We removed the existing boot flashings so that we could seal directly to the conduit or steel posts.”

Gutters, Lightning Protection and Safety Systems

The large commercial gutters also needed to be refurbished. The gutters were 4 feet deep and 4 feet wide, and were outfitted with a cable snowmelt system, which had to be removed. “The gutters had a lot of damaged insulation, so material in the gutter sections was 100 percent torn off,” notes Vetrovsky.

After the roof surface was cleaned, the restoration system was applied. The three step process consists of a primer, a base coat with a fiberglass mat embedded in it, and a topcoat. Photos: Tremco Roofing and Building Maintenance

In the gutters, tapered insulation was installed, and a cover board — DensDeck from Georgia-Pacific — was added for increased durability. New EPDM membrane was installed and cleaned prior to the three-step coating application. New heat trace cable was also installed.

The lightning protection system also required repair, and close coordination with the subcontractors was critical. “The existing lightning protection had to be removed to apply the new roof system, but we couldn’t remove it 100 percent, because we still had to have an active lightning protection system for the building,” says Vetrovsky. “We rearranged the lightning system and installed new stanchions to try to eliminate as many horizontal lines as we could.”

During construction, key to the safety plan was a perimeter barrier system, which was installed by workers who were 100 percent tied off. After the system was in place, workers inside the barricades did not need to wear personal fall arrest systems. “The entire perimeter had a barricade system put on before any material was even loaded,” Vetrovsky says. The company makes its own barricade sections, which are anchored to the parapet walls and gravel stop edges and feature a downward leg for added support.

As part of the project, crews also installed permanent safety equipment. “There was an existing tie-off system out there, but it was not a certified system and we couldn’t use it,” Vetrovsky says. “We brought that to the owner’s attention and replaced it with a new certified tie-off system manufactured by Guardian Safety.”

Challenging Schedule

Progressive Field and the Quicken Loans Arena are right next to each other, and logistics and scheduling around the stadiums was difficult. Work began in 2016 and finished in 2017, and the demanding schedule was made even more difficult when both the Indians and the Cavaliers made deep runs into the playoffs. In 2016, the Cavs became NBA Champions. But it was the Indians making it to the 2016 World Series that posed bigger logistical problems for the re-roofing project.

The restored roof recreates the original color scheme, which features three different custom colors. The main roof is light gray, with black under the large LED sign, while the sections over the wings stripes are white. Photos: Tremco Roofing and Building Maintenance

“The first part of the schedule was the most difficult, as we had the get the black coating on the roof under the sign prior to the playoffs,” Vetrovsky says. The sign covered approximately 30,000 square feet of roof area, and it was difficult to access the roof surface beneath it. “Crews had to work on their hands and knees to apply the coating beneath the steel framing. That was towards the fall, when the weather started changing, and one of the biggest hurdles was just getting the roof dry in the morning. It got colder and colder as we got down to the wire, but we made our deadline for the work under the sign.”

The staging area was also limited, and the crane could only lift material to one section of the roof. Some material had to be moved by hand some 2,000 feet. “It was an awfully long walk from one end of that roof to the other,” Vetrovsky recalls.

Concerts and other events held during the construction cycle made the schedule even more challenging. “The most notable event was probably the Republican National Convention, which totally shut the site down for more than a week because of security,” notes Slattery.

Concerts usually necessitated loading in the early morning and clearing the staging area by 8 a.m., but usually work could continue during the day. “We had to do a lot of coordination to make sure we had what we needed to work the entire day and also not go against our commitment to the owner that we would not work past certain hours,” Vetrovsky says. “Many of the special events started after 7 p.m., so we would be long gone by then.”

Championship Caliber

The project was wrapped up earlier this year. Vetrovsky and Slattery agree that the system chosen was a great fit for this project for several reasons. With restoration, there is less noise, less disruption, and less equipment than with a re-roofing project, and the roof has a warranty for the next 20 years. The process also limits negative impact on the environment by preventing removal and disposal of the old roof system.

“The weight was also a factor,” notes Vetrovsky. “With the existing structure, there wasn’t a lot of room for a different type of roof system with heavy cover boards. This roof system was perfect because it doesn’t add a lot of weight.”

The coating also minimized installation time, notes Slattery. “The disruption of a roof replacement in a hospitality setting like that, where they need 250 days of revenue stream, restoration becomes a real attractive option,” he says. “I can’t think of one day where we really disrupted anything.”

Vetrovsky points to his talented crews as the key to meeting tough schedules with top-quality production “What we can offer is skilled labor,” he says. “We’re a union contractor and our guys are well trained. The harder, the better for us. We can handle projects that most other contractors won’t even put a number to — this project being one of those.”

He credits Adam Livingston, a third-generation foreman for Warren Roofing, for his work on the project. “With his experience and attention to detail, we were able to complete this project on time, meet the expectations of the client and Tremco, and match the unique aesthetic requirements of the roof,” says Vetrovsky. “We have a lot of great employees who take pride in their work. Take all of that together, that’s why we can be successful on projects like the Quicken Loans Arena.”

The Cavaliers taking the NBA Championship during the project only added to the excitement. “It’s a great feather in our cap,” notes Slattery. “Restoration is a growing segment of the market. Instead of letting the clock run out on these roofs, if you catch them at the right time, it can be a phenomenal way to keep costs down and it’s good for the environment because it’s not adding waste to landfills.”

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May/June 2020

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About Roofing

Roofing is a national publication that unravels, investigates and analyzes how to properly design, install and maintain a roof system. Through the voices of professionals in the field, Roofing’s editorial provides a unique perspective.